tablet-app/lib/Screens/PDF/pdf_view.dart

import 'dart:async';
import 'dart:convert';
import 'dart:io';
//import 'dart:html';
import 'dart:ui' as ui;

import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter_pdfview/flutter_pdfview.dart';
import 'package:manager_api/api.dart';
import 'package:path_provider/path_provider.dart';
import 'package:tablet_app/Components/loading_common.dart';


class PDFViewWidget extends StatefulWidget {
  final SectionDTO? section;
  PDFViewWidget({this.section});

  @override
  _PDFViewWidget createState() => _PDFViewWidget();
}

class _PDFViewWidget extends State<PDFViewWidget> {
  PdfDTO pdfDTO = PdfDTO();
  String remotePDFpath = "";
  final Completer<PDFViewController> _controller = Completer<PDFViewController>();
  int? pages = 0;
  int? currentPage = 0;
  bool isReady = false;
  String errorMessage = '';
  ValueNotifier<Map<String, int>> currentState = ValueNotifier<Map<String, int>>({'page': 0, 'total': 0});

  @override
  void initState() {
    print(widget.section!.data);
    pdfDTO = PdfDTO.fromJson(jsonDecode(widget.section!.data!))!;
    print(pdfDTO);
    super.initState();

    /*createFileOfPdfUrl(pdfDTO.source_!).then((f) {
      setState(() {
        remotePDFpath = f.path;
        print("paaath");
        print(remotePDFpath);
      });
    });*/
  }

  Future<File> createFileOfPdfUrl(String source_) async {
    Completer<File> completer = Completer();
    print("Start download file from internet!");
    try {
      // "https://berlin2017.droidcon.cod.newthinking.net/sites/global.droidcon.cod.newthinking.net/files/media/documents/Flutter%20-%2060FPS%20UI%20of%20the%20future%20%20-%20DroidconDE%2017.pdf";
      // final url = "https://pdfkit.org/docs/guide.pdf";
      final url = source_;
      final filename = url.substring(url.lastIndexOf("/") + 1);
      var request = await HttpClient().getUrl(Uri.parse(url));
      var response = await request.close();
      var bytes = await consolidateHttpClientResponseBytes(response);
      var dir = await getApplicationDocumentsDirectory();
      print("Download files");
      print("${dir.path}/$filename");
      File file = File("${dir.path}/$filename");

      await file.writeAsBytes(bytes, flush: true);
      completer.complete(file);
    } catch (e) {
      throw Exception('Error parsing asset file!');
    }

    return completer.future;
  }

  @override
  void dispose() {
    //_webView = null;
    super.dispose();
  }


  @override
  Widget build(BuildContext context) => pdfDTO.resourceUrl != null && pdfDTO.resourceUrl!.length > 0 ?
  FutureBuilder(
    future: createFileOfPdfUrl(pdfDTO.resourceUrl!),
    builder: (context, AsyncSnapshot<dynamic> snapshot) {
      print("snapshot.data");
      print(snapshot.data);
      if (snapshot.connectionState == ConnectionState.done) {
        return Stack(
          children: [
            PDFView(
              filePath: snapshot.data.path,
              enableSwipe: true,
              swipeHorizontal: true,
              autoSpacing: true,
              pageFling: true,
              fitPolicy: FitPolicy.HEIGHT,
              onRender: (_pages) {
                //setState(() {
                  pages = _pages;
                  isReady = true;
                //});
              },
              onError: (error) {
                print(error.toString());
              },
              onPageError: (page, error) {
                print('$page: ${error.toString()}');
              },
              onViewCreated: (PDFViewController pdfViewController) {
                //_controller.complete(pdfViewController);
              },
              onPageChanged: (int? page, int? total) {
                currentPage = page;
                pages = total;
                currentState.value = {'page': page!, 'total': total!};

                print('page change: $page/$total');
              },
            ),
            Positioned(
                bottom: 20,
                right: 20,
                child: ValueListenableBuilder<Map<String, int>>(
                  valueListenable: currentState,
                  builder: (context, value, _) {
                    return Container(
                      //color: Colors.blueAccent,
                      child: Text("${value["page"]!+1}/${value["total"]!}",
                          style: TextStyle(color: Colors.black, fontSize: 30))
                    );
                  },
                ),
            ),
          ],
        );
      } else {
        return Center(
            child: Container(
                child: LoadingCommon()
            )
        );
      }
    }
  ) :
  Center(child: Text("Le PDF ne peut pas être affiché, il n'existe pas"));
} //_webView